Abstract: This chapter describes the basic features of the American free speech doctrine and then considers its application to various forms of extreme speech. This analysis reveals that most of the speech restrictions considered in this book, while consistent with the constitutional norms of other democracies, would be unconstitutional in the U.S. The leitmotif of contemporary American free speech doctrine is its intense hostility to content regulation of public discourse, particularly viewpoint regulation. In addition, Brandenburg v. Ohio narrowly confines governmental power to punish the advocacy of law violation. Hate speech bans, whether in the form of public order regulations, prohibitions against group defamation, or bans on Holocaust denial, would be deemed unconstitutional. Under Brandenburg, laws that prohibit mere advocacy of terrorism would also be held to violate the First Amendment. The chapter concludes that much of the explanation for American free speech exceptionalism lies in the U.S. Supreme Court's extensive experience with free speech issues, particularly the lessons it learned from its failure to protect adequately dissent in the early part of the 20th century.

Keywords: content regulation, viewpoint discrimination, public discourse, Brandenburg v. Ohio, hate speech, group defamation, Holocaust denial, advocacy of terrorism, First Amendment, American free speech exceptionalism,